package main

import "os"

func main() {
	/*
		f, err := os.Create("./test.txt")
		if err != nil {
			println("create err:", err)
			return
		}
		defer f.Close()
		println("successful")
		n, err := f.WriteString("*****")
		if err != nil {
			println("writer err:", err)
			return
		}
		println("write:", n, "char")*/
	f, err := os.Open("./test.txt")
	if err != nil {
		println("file open err:", err)
		return
	}
	_, err = f.WriteString("+++++")
	if err != nil {
		println("write err:", err)
		return
	}
	println("sucessful")
}
